This application is based upon and claims the benefit of priority from the prior Japanese Patent Application No. 2000-131860, filed Apr. 28, 2000, the entire contents of which are incorporated herein by reference.
The present invention relates to an information processing apparatus and system, and power saving method for the system and, more particularly, to a technique of detecting the non-use state of the apparatus main body and switching the operation mode of a peripheral device by radio communication in accordance with the detection result.
As disclosed in Jpn. Pat. Appln. KOKAI Publication No. 9-282067, some of information processing terminals such as a PC (Personal Computer), and some of peripheral devices such as a keyboard and mouse (pointing device for inputting a manipulation quantity) comprise a radio communication function. Such devices are connected by radio, and data are communicated between the connected devices. A wireless information processing apparatus or peripheral device having the radio communication function is free from obstruction of a cable, can be freely installed within a radio communicable distance, and can increase the operability, compared to cable connection between devices.
Many of peripheral devices having the radio communication function are driven by batteries in terms of cable-less operation, and power consumption must be reduced to ensure a longer operation time. However, in communicating data using the radio communication function, the radio communication function consumes large power. For this reason, peripheral devices such as a wireless keyboard and wireless mouse have a power saving mode for reducing power consumption in addition to a normal operation mode.
One of methods of shifting to the power saving mode for reducing power consumption in a conventional information processing apparatus using a wireless keyboard uses time measurement means for starting time measurement operation when key input by the operator stops. If the time measurement means detects the lapse of a predetermined time, power supplies other than one for a circuit necessary for resuming the operation are turned off to reduce consumption of the battery power. As another method, means for shifting the operation mode to the power saving mode in accordance with key input is employed, and the operator key-inputs a predetermined instruction to shift the mode to the power saving mode.
The method of shifting the mode to power saving mode upon detection of the lapse of a predetermined time after key input stops requires a predetermined time till shift to the power saving mode. During the predetermined time, the power consumption state does not change, and power is wastefully consumed. If a book or the like is placed on the wireless keyboard, a key is erroneously operated. In this case, the apparatus cannot stay in the power saving mode, wastefully consuming power. Similarly, if the operation key of a wireless mouse is erroneously pressed, the apparatus cannot stay in the power saving mode, wastefully consuming power.
In the method in which the operator inputs an instruction to shift the operation mode to the power saving mode, when a plurality of devices are to be shifted to the power saving mode, the operation must be repeated for the number of devices to be shifted, which makes the operation very cumbersome. If the operator forgets to perform an operation, these devices remain in the normal mode, and wastefully consume power.
It is an object of the present invention to provide an information processing apparatus and system, and power saving method for the system that can reliably prevent wasteful power consumption.
According to a first aspect of the present invention, there is provided an information processing apparatus comprising:
an information processing section switchable between a first state and a second state in which power consumption is lower than in the first state;
a communication section configured to allow radio communication between the information processing section and a peripheral device, the peripheral device being switchable between a third state and a fourth state in which power consumption is lower than in the third state; and
a controller configured to control the peripheral device via the communication section so as to set the peripheral device in the third state when the information processing section is in the first state, and set the peripheral device in the fourth state when the information processing section is in the second state.
According to a second aspect of the present invention, there is provided an information processing system comprising:
an information processing apparatus having an information processing section switchable between a first state and a second state in which power consumption is lower than in the first state;
a peripheral device switchable between a third state and a fourth state in which power consumption is lower than in the third state;
a communication section configured to allow radio communication between the information processing section and the peripheral device; and
a controller configured to control the peripheral device via the communication section so as to set the peripheral device to the third state when the information processing section is in the first state, and set the peripheral device to the fourth state when the information processing section is in the second state.
According to a third aspect of the present invention, there is provided a power saving method in an information processing system, comprising the steps of:
switching an information processing section of an information processing apparatus between a first state and a second state in which power consumption is lower than in the first state;
switching a peripheral device between a third state and a fourth state in which power consumption is lower than in the third state, the peripheral device communicating with the information processing section via a communication section by radio; and
controlling the peripheral device via the communication section so as to set the peripheral device in the third state when the information processing section is in the first state, and set the peripheral device in the fourth state when the information processing section is in the second state.
Additional objects and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out hereinafter.